iPhone Wifi high latency in ping times

Discussion in 'iPhone Tips, Help and Troubleshooting' started by Nektarios, Apr 29, 2008.

  1. Nektarios macrumors newbie

    Joined:
    Apr 29, 2008
    #1
    Hello,

    I discovered that iPhone has a problem with it's wifi. It has extremely high latency which I cannot explain why.

    The problem:

    Desktop computer is connected with Gigabit ethernet to the router
    iPhone Jailbroken with pwnage tool, 1.1.4 fw, 3.9 bootloader.
    iPhone is connected with 802.11g WPA2 Wifi at the same router with perfect signal.

    Pinging from the desktop computer (or from anywhere else on the LAN) to iPhone with ip 192.168.1.75:

    ping 192.168.1.75

    Reply from 192.168.1.75: bytes=32 time=55ms TTL=64
    Reply from 192.168.1.75: bytes=32 time=79ms TTL=64
    Reply from 192.168.1.75: bytes=32 time=511ms TTL=64
    Reply from 192.168.1.75: bytes=32 time=22ms TTL=64
    Reply from 192.168.1.75: bytes=32 time=1274ms TTL=64

    As you can see these pings have high latency and extreme jittering (55ms->1274ms) for a LAN, with inconsistency and packet loss.
    I have tried this on 5 different wifi routers and 2 different LANs and on all of them the problem is the same. I have also tried it on my windows xp laptop's wifi as ad hoc connection and it was perfect with only 1ms average ping time, which is exactly how much it should be! So I guess there's an incompatibility with the iPhone's wifi implementation (software or hardware) and the router's wifi access point.

    The problem is that iPhone is such a GREAT piece of hardware/software which I really LOVE, but with such high ping times the difference in web browsing/email etc is enormous. In other words it could be so much faster if this bug was corrected!
    I am a competent programmer and I know my fair share of networking, but I really cannot find what is going wrong here.
    Can someone help pinpoint this problem and helpfully eliminate it?

    Post your pings and router brand and model so we can at least see which one's have it and which one's do not.

    Thanks in advance.
     
  2. Oskee2001 macrumors regular

    Joined:
    Feb 14, 2008
  3. Nektarios thread starter macrumors newbie

    Joined:
    Apr 29, 2008
    #3
    There's high latency on iPhone's Wireless (Wifi), it should be at 3ms at most but it's 500ms and that's the problem I am talking about. I know my post is a little technical but that's why I posted it here so I can discuss it with more technical-inclined people.
     
  4. zmit macrumors regular

    Joined:
    Apr 12, 2008
    #4
    pinging from my macbook to the iphone through an airport express
    (our network is complicated though.. need to fix that...)

    64 bytes from 10.0.0.92: icmp_seq=0 ttl=64 time=3.213 ms
    64 bytes from 10.0.0.92: icmp_seq=1 ttl=64 time=3.279 ms
    64 bytes from 10.0.0.92: icmp_seq=2 ttl=64 time=18.721 ms
    64 bytes from 10.0.0.92: icmp_seq=3 ttl=64 time=141.678 ms
    64 bytes from 10.0.0.92: icmp_seq=4 ttl=64 time=2.786 ms
    64 bytes from 10.0.0.92: icmp_seq=5 ttl=64 time=2.390 ms
    64 bytes from 10.0.0.92: icmp_seq=6 ttl=64 time=3.076 ms
    64 bytes from 10.0.0.92: icmp_seq=7 ttl=64 time=31.658 ms
    64 bytes from 10.0.0.92: icmp_seq=8 ttl=64 time=9.461 ms
    64 bytes from 10.0.0.92: icmp_seq=9 ttl=64 time=2.661 ms

    --- 10.0.0.92 ping statistics ---
    10 packets transmitted, 10 packets received, 0% packet loss
    round-trip min/avg/max/stddev = 2.390/21.892/141.678/40.955 ms
     
  5. isianto macrumors regular

    Joined:
    Feb 12, 2007
    Location:
    Indonesia
    #5
    what's your iphone distance to the ap?
    the one thing that I can think of are:
    1. The distance between ap and iphone
    2. The network itself is slow, can be checked using traceroute to see which device/network is slow.
    I hope you're understand what I'm saying.
     
  6. Nektarios thread starter macrumors newbie

    Joined:
    Apr 29, 2008
    #6
    I have already tested and excluded both of these as I did with other common factors that can interfere. The distance is irrelevant, even in < 1 meter away and ofcourse all the other devices in the LANs are at 1ms ping with no problems at all, this is double checked.

    Should I assume that you don't have this problem? Did you test the ping to your iPhone?
     
  7. zmit macrumors regular

    Joined:
    Apr 12, 2008
    #7
    so your delay is between the iphone and the AP?
     
  8. Van Wildonher macrumors 6502a

    Joined:
    Apr 29, 2008
    #8
    That's what it says.
     
  9. EspressoLove macrumors 6502

    EspressoLove

    Joined:
    Jun 29, 2007
    Location:
    Bay Area
    #9
    Same here, ping to iPhone :

    PING 192.168.0.156 (192.168.0.156): 56 data bytes
    64 bytes from 192.168.0.156: icmp_seq=0 ttl=64 time=118.549 ms
    64 bytes from 192.168.0.156: icmp_seq=1 ttl=64 time=40.059 ms
    64 bytes from 192.168.0.156: icmp_seq=2 ttl=64 time=473.773 ms
    64 bytes from 192.168.0.156: icmp_seq=3 ttl=64 time=501.897 ms
    64 bytes from 192.168.0.156: icmp_seq=4 ttl=64 time=531.897 ms
    64 bytes from 192.168.0.156: icmp_seq=5 ttl=64 time=342.740 ms
    64 bytes from 192.168.0.156: icmp_seq=6 ttl=64 time=57.954 ms
    64 bytes from 192.168.0.156: icmp_seq=7 ttl=64 time=288.092 ms
    64 bytes from 192.168.0.156: icmp_seq=8 ttl=64 time=112.002 ms
    64 bytes from 192.168.0.156: icmp_seq=9 ttl=64 time=130.167 ms

    --- 192.168.0.156 ping statistics ---
    10 packets transmitted, 10 packets received, 0% packet loss
    round-trip min/avg/max/stddev = 40.059/259.713/531.897/182.686 ms
     
  10. EspressoLove macrumors 6502

    EspressoLove

    Joined:
    Jun 29, 2007
    Location:
    Bay Area
    #10
    For a comparison, here how it should be (ping to my MBP) :

    Ping has started ...

    PING 192.168.0.104 (192.168.0.104): 56 data bytes
    64 bytes from 192.168.0.104: icmp_seq=0 ttl=64 time=39.575 ms
    64 bytes from 192.168.0.104: icmp_seq=1 ttl=64 time=1.470 ms
    64 bytes from 192.168.0.104: icmp_seq=2 ttl=64 time=1.140 ms
    64 bytes from 192.168.0.104: icmp_seq=3 ttl=64 time=6.613 ms
    64 bytes from 192.168.0.104: icmp_seq=4 ttl=64 time=0.951 ms
    64 bytes from 192.168.0.104: icmp_seq=5 ttl=64 time=1.098 ms
    64 bytes from 192.168.0.104: icmp_seq=6 ttl=64 time=1.094 ms
    64 bytes from 192.168.0.104: icmp_seq=7 ttl=64 time=1.209 ms
    64 bytes from 192.168.0.104: icmp_seq=8 ttl=64 time=1.090 ms
    64 bytes from 192.168.0.104: icmp_seq=9 ttl=64 time=1.003 ms

    --- 192.168.0.104 ping statistics ---
    10 packets transmitted, 10 packets received, 0% packet loss
    round-trip min/avg/max/stddev = 0.951/5.524/39.575/11.468 ms
     
  11. EspressoLove macrumors 6502

    EspressoLove

    Joined:
    Jun 29, 2007
    Location:
    Bay Area
    #11
    It is with MBP downloading a bunch of stuff right now, and iPhone doing nothing.... :(
     
  12. EspressoLove macrumors 6502

    EspressoLove

    Joined:
    Jun 29, 2007
    Location:
    Bay Area
    #12
    What funny is, on WiFi network created to test tethering, i got these :
    (Ping from MB to iPhone)

    PING 169.254.61.68 (169.254.61.68): 56 data bytes
    64 bytes from 169.254.61.68: icmp_seq=0 ttl=255 time=5.087 ms
    64 bytes from 169.254.61.68: icmp_seq=1 ttl=255 time=2.076 ms
    64 bytes from 169.254.61.68: icmp_seq=2 ttl=255 time=2.041 ms
    64 bytes from 169.254.61.68: icmp_seq=3 ttl=255 time=2.130 ms
    64 bytes from 169.254.61.68: icmp_seq=4 ttl=255 time=2.014 ms
    64 bytes from 169.254.61.68: icmp_seq=5 ttl=255 time=2.045 ms
    64 bytes from 169.254.61.68: icmp_seq=6 ttl=255 time=1.983 ms
    64 bytes from 169.254.61.68: icmp_seq=7 ttl=255 time=4.280 ms
    64 bytes from 169.254.61.68: icmp_seq=8 ttl=255 time=2.202 ms
    64 bytes from 169.254.61.68: icmp_seq=9 ttl=255 time=2.051 ms

    --- 169.254.61.68 ping statistics ---
    10 packets transmitted, 10 packets received, 0% packet loss
    round-trip min/avg/max/stddev = 1.983/2.591/5.087/1.063 ms
     
  13. zmit macrumors regular

    Joined:
    Apr 12, 2008
    #13
    so thats a direct connection.....

    heres my results with my airport express.
    MB>airport>iphone

    PING 10.0.0.92 (10.0.0.92): 56 data bytes
    64 bytes from 10.0.0.92: icmp_seq=0 ttl=64 time=68.698 ms
    64 bytes from 10.0.0.92: icmp_seq=1 ttl=64 time=93.097 ms
    64 bytes from 10.0.0.92: icmp_seq=2 ttl=64 time=14.111 ms
    64 bytes from 10.0.0.92: icmp_seq=3 ttl=64 time=37.901 ms
    64 bytes from 10.0.0.92: icmp_seq=4 ttl=64 time=61.817 ms
    64 bytes from 10.0.0.92: icmp_seq=5 ttl=64 time=85.735 ms
    64 bytes from 10.0.0.92: icmp_seq=6 ttl=64 time=7.245 ms
    64 bytes from 10.0.0.92: icmp_seq=7 ttl=64 time=30.359 ms
    64 bytes from 10.0.0.92: icmp_seq=8 ttl=64 time=158.786 ms
    64 bytes from 10.0.0.92: icmp_seq=9 ttl=64 time=68.242 ms

    even that isnt that great..... the only thing i can think of, is that apple have integrated a HELL OF A LOT of error-correcting to ensure things dont get dropped....
    or they just suck with wifi....

    another comparison.
    MB>Dlink AP>iphone

    PING 192.168.0.100 (192.168.0.100): 56 data bytes
    64 bytes from 192.168.0.100: icmp_seq=0 ttl=64 time=114.958 ms
    64 bytes from 192.168.0.100: icmp_seq=1 ttl=64 time=87.010 ms
    64 bytes from 192.168.0.100: icmp_seq=2 ttl=64 time=270.099 ms
    64 bytes from 192.168.0.100: icmp_seq=3 ttl=64 time=32.961 ms
    64 bytes from 192.168.0.100: icmp_seq=4 ttl=64 time=9.975 ms
    64 bytes from 192.168.0.100: icmp_seq=5 ttl=64 time=185.230 ms
    64 bytes from 192.168.0.100: icmp_seq=6 ttl=64 time=157.291 ms
    64 bytes from 192.168.0.100: icmp_seq=7 ttl=64 time=281.302 ms
    64 bytes from 192.168.0.100: icmp_seq=8 ttl=64 time=318.425 ms
    64 bytes from 192.168.0.100: icmp_seq=9 ttl=64 time=23.552 ms

    and then via adhoc
    MB>iphone

    PING 169.254.93.163 (169.254.93.163): 56 data bytes
    64 bytes from 169.254.93.163: icmp_seq=0 ttl=255 time=6.656 ms
    64 bytes from 169.254.93.163: icmp_seq=1 ttl=255 time=1.799 ms
    64 bytes from 169.254.93.163: icmp_seq=2 ttl=255 time=285.427 ms
    64 bytes from 169.254.93.163: icmp_seq=3 ttl=255 time=9.823 ms
    64 bytes from 169.254.93.163: icmp_seq=4 ttl=255 time=1.689 ms
    64 bytes from 169.254.93.163: icmp_seq=5 ttl=255 time=2.137 ms
    64 bytes from 169.254.93.163: icmp_seq=6 ttl=255 time=2.651 ms
    64 bytes from 169.254.93.163: icmp_seq=7 ttl=255 time=437.631 ms
    64 bytes from 169.254.93.163: icmp_seq=8 ttl=255 time=5.749 ms
    64 bytes from 169.254.93.163: icmp_seq=9 ttl=255 time=11.634 ms

    that was about a foot away!
     
  14. outz macrumors 6502

    Joined:
    Jul 17, 2007
    #14
    i know this is an old thread, but i noticed my 3g iphone was having the same extremely high wifi latency my old iphone had... for me, the high latency is only there when the phone isn't rx/tx anything... once i start a large download or upload on the phone the pings to it jump down to a steady 2ms. perhaps it is a power saving method? it lowers the wifi chipset power when not in use and that results in crazy high/unstable latency?
     
  15. rvjr macrumors newbie

    Joined:
    Oct 25, 2008
    #15
    Wow, same here!

    Hi guys,

    same here, with a first generation iPhone and a Vista ad-hoc host. The problem didn't occur with XP though... And, I also had the phenomena that when I joined another XP machine into the ad-hoc network between the Vista machine and the iPhone, the pings were ok again (meaning <5ms), but that only happend once and I couldn't reproduce it...

    Also strange: there is a very regular pattern: it starts at around 25ms latency and goes up to 210ms, then starts all over again...

    Pinging 192.168.0.2 with 32 bytes of data:
    Reply from 192.168.0.2: bytes=32 time=210ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=28ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=50ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=73ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=96ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=119ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=142ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=165ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=188ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=211ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=29ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=52ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=75ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=98ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=121ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=144ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=167ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=190ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=213ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=31ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=54ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=77ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=100ms TTL=64

    Anyone suggestions how to solve this?

    Regards
    Rainer
     
  16. rvjr macrumors newbie

    Joined:
    Oct 25, 2008
    #16
    [solved]

    Ok, sorry for bugging you. That was actually easy to solve for me: Computer Managment -> Device Manager -> Network Adapters -> Wifi Card (Intel WifiLink 5100 for me) -> Properties -> Advanced -> Ad-Hoc Power Managent -> Disabled

    That was the only setting that worked for me, but now my pings are these:

    Pinging 192.168.0.2 with 32 bytes of data:
    Reply from 192.168.0.2: bytes=32 time=4ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=1ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=2ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=1ms TTL=64
    Reply from 192.168.0.2: bytes=32 time=1ms TTL=64

    I hope disabling power management also helps you, even if you're on different hardware.

    Bye
    Rainer
     
  17. jazzwhistle macrumors newbie

    Joined:
    Nov 5, 2008
    #17
    The same youtube clip takes 5 mins on Wifi, 2 mins on 3G!

    I started checking this out when I noticed youtube downloading exceptionally slowly on my home wifi, slower than 3G... I'm using the latest 16Gb iPhone 2.1(5F136) and a Linksys WRT54GSv4 with the latest Firmware 1.06.3. Distance from the router makes no difference to these pathetic speeds, and I've tried changing the DNS to the router IP to no avail.

    For those who dont "ping", downloading a 1min46 video clip on youtube takes:

    5 minutes on iPhone Wifi
    2 minutes on iPhone 3G
    30 seconds on Macbook Wifi

    For those who do, here are my pings between Router and iPhone, between Macbook and iPhone, both while downloading from youTube on iPhone, and while idle:

    Linksys > iPhone while downloading from youtube:
    Linksys > iPhone, idle:

    Macbook > Linksys > iPhone downloading from youtube:

    And finally... Macbook > Linksys > iPhone, idle:

    Help!!
     
  18. Resist macrumors 68030

    Joined:
    Jan 15, 2008
    #18
    I know this is kind of an old thread but, I also noticed slow download speeds on my iPhone 3G compared to my laptop over my home WiFi. My Cable Internet is 10meg download service and my desktop (wired) and laptop (wireless) get that speed most of the time. But for some reason my iPhone 3G gets only 6meg at the most and usually is around 3megs. I don't understand why the iPhone is so much slower.
     
  19. xStatiCa macrumors regular

    Joined:
    Oct 7, 2009
    #19
    Yes I am resurrecting this thread...

    I noticed the same latency when my iPad 2 is idle. 40 - 200+ms pings from the router. Pinging my macbook air was 3ms from the router. I at first was concerned about such horrible pings for the local wifi.

    I just tested the Galaxy Tab 10.1 and it had the same results when it was idle. 40 - 200+ms pings when idle.

    The second I request something from the internet on either mobile device the pings go down immediately to 3ms or so to match the macbook air.

    The person above who mentioned power savings got it right. When the device is idle the wifi hardware goes into a powersave mode because it isn't critical to get data quickly. When network data is needed the wifi hardware is taken out of power save mode until network traffic is reduced to an idle state again so that power save mode is kicked back in.
     
  20. beej69 macrumors member

    Joined:
    Nov 22, 2003
    Location:
    Puerto Rico
    #20
    me, too :)

    i'm seeing this latency on a 4S running iOS 5.0.1.

    fascinating info and maybe it explains what you're seeing, but i'm still seeing ridiculously high latency between a MBA and my iphone over wi-fi even when the device is, say, downloading a youtube movie. my AP is an AirPort Express, so one would think the environment has been heavily tested...

    i don't see the same behavior when i ping the iphone using USB tethering, so that kind of rules out something affecting the networking stack, in general. pings from the iphone to outside hosts like google.com are about 7 times as slow as the same pings from my MBA, which is bad, but nowhere near as bad as the multiple-hundred-ms latencies i see between MBA and iphone.

    anybody have other theories?

    ----------

    just to get other data points, could somebody who doesn't think they have this problem and are jailbroken post the result of a ping from their phone to their AP?

    you'll need the inetutils package to get ping.

    thanks!
    marc
     
  21. blatopilot macrumors regular

    Joined:
    Sep 24, 2011
    #21
    Here is a suggestion. Turn off cell network search and see what you get. It is in location services. See pictures below.

    Not claiming remedy as my iphone 4s is not jailbroken, but this little test made my iphone network experience go from junk to working like the first day I got it.
     

    Attached Files:

  22. beej69 macrumors member

    Joined:
    Nov 22, 2003
    Location:
    Puerto Rico
    #22
    thanks for the suggestion. no discernable difference with that change, here :(

    any other ideas?
     
  23. Mickaël macrumors newbie

    Joined:
    Jan 30, 2013
    #23
    My turn to resurrect the thread...

    I am developing an application that requires low latency between a mobile device and a PC.
    When it comes to using any Apple device (currently tested with an iPhone and two iPads 2) there is a huge networking problem... It looks like the Apple devices are only capable of sending data at a rate of 3-4 frames per second, and while they are sending data their ping times raise to 200-300ms. If the same ping is done without transferring data, they keep in the 2-5ms zone.

    I tested the same use case with Samsung devices (both smartphones and tablets) and the problem does not appear. On the mobile device, data is sent using websockets in Javascript while the data is being handled on the PC in a C++ app. Does anyone has experienced something similar? Does someone has a hint on what can be going wrong?
     
  24. Pentos macrumors newbie

    Joined:
    Mar 28, 2013
    #24
    I experience the same problem with an Ipad mini. Is someone find a solution?
     
  25. beej69 macrumors member

    Joined:
    Nov 22, 2003
    Location:
    Puerto Rico
    #25
    still seeing crappy pings with an iPhone 5s running iOS 7.0.2 using a DD-WRT access point between my MBA and the phone :(

    it really is too bad that Apple has such ****** support...
     

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